Friday, May 17th

Make room in the hut for Lu/Catie’s instrument

Catastrophe! While slightly moving the NPL tank, a short-circuit happened. I saw sparks and the GC/MS stopped. Everything that was connected to CKT 10 stopped. Strange thing, the fast NOx instrument stopped as well (at least the UPS + fan of H20 pump + laptop). NO flow on fast O3 instrument dropped to 0. I think the line between the NPL tank and the GC/MS touched CKT 10 and that’s how everything happened (see pics below). Jacques and I disconnected everything (computer, GC/MS, UPS) from CKT 10 and connected to CKT 17 instead. GC/MS restarted, fast NOx as well. We will check tomorrow that everything is indeed okay.

The NO flow dropping to 0 on the fast O3 has actually nothing to do with the short-circuit. The needle valve was not sufficiently open. Problem fixed. Keep an eye on this NO flow to make sure it doesn’t drop to 0 again.

Pics of the NPL tank line, CKT 10 and floor below CKT 10.

Fast systems

  • pump box outside and protected from rain.
  • fast O3 and NOx restarted
  • The fast NOx PMT temperature was too high, that was because the H20 pump was not working properly (air bubbles). Problem fixed.
  • The O2 flow on the fast NOx is highly variable (from 170 to 200). Don’t know why. After lunch, varies from 190 to 200. Keep an eye on that in the next couple days.
  • Background on fast NOx seems pretty high - Double check that tomorrow.
  • Double-checked that fast NOx is sampling from outside (cf high background). Here is what I have:
  • Double-checked that zero air is connected to fast NOx system and zero air tank opened.
  • Save fast NOx data on fast O3 laptop: USB-serial cables (COM 15 on fast O3, COM 8 on fast NOx) connected by NULL modem cable. Jacques is updating the VIs to make the data transfer possible.

Flux hut upgrades

Thursday, May 16th

I made it to Toolik after a 10hr-drive. There’s still snow in Atigun Pass but snow is gone pretty much everywhere else.